Humidifier housing unit



FIG. 1 is a perspective view of the design for a humidifier housing unit in accordance with the present invention;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a left side elevational view thereof;

FIG. 5 is a right side elevational view thereof;

FIG. 6 is a bottom plan view thereof; and,

FIG. 7 is a top plan view thereof.

The broken-line showing of environmental structure in FIGS. 1-6 is for illustrative purposes only and forms no part of the claimed design. 

The ornamental design for a humidifier housing unit, as shown and described. 